Grinding-rolls



E. F. CLARK.

GRINDING ROLLS.

APPLICATION FILED NOV.19, 19m.

1 ,360,887. V Patented Nov. 30, 1920.

l/YVE/YTOR EDWHRD F CLHRK.

EDWARD r. CLARK, or MINNEAPOLIS, MINNESOTA.

GRINDING-ROLLS.

Application filed November 19, 1918. Serial No. 263,145.

To all whom z'tmay concern: 7 Be it known that I, EDWARD F. CLARK,

a citizen of the United States, resident of Minneapolis, in the county of Hennepin and State of Minnesota, have inventedcertain new and useful Improvements in Grinding- Rolls, of which the following is a specification.

My invention relates to improvements in rolls for grinding wheat or other grain.

The invention consists generally in grinding rolls having the construction and char acteristics hereinafter described and particularly pointed out in the claims.

In the accompanying drawing forming part of this specification,-

Figure 1 is a plan view of a pair of grinding rolls embodying my invention,

Fig. 2 is an end elevation of the same.

Fig. 8 is adetail elevation on a larger scale of a single roll embodying the novel construction,

Fig. 4 is a detail plan View showing the grinding roll of novel construction in grinding relation to a grinding roll having straight corrugations,

ig. 5 is a perspective view on a larger scale showing in detail a few of the interrupted ribs.

In carrying out my present invention I employ a grinding roll 1 of any preferred size and of the usual material with a series of corrugations 2, extending parallel to each other and spirally of the roll, with asecond series of corrugations 3 extending parallel to each other and spirally of the roll at an angle to the corrugations 2, and I employ in grinding contact with said roll a second grinding roll 4 which may be of any ordinary or preferred construction.

I have shown in the drawings the second grinding roll 4 as provided in Fig. 1 with a series of spiral corrugations 5 and I have shown in Fig. 4 the roll 4 providedwith straight corrugations 6. I do not limit myself to any particular arrangement of the corrugations on the roll 4. These corrugations may be of any preferred shape and they may extend longitudinally of the roll parallel to the axis or they may extend spirally at any desired pitch or degree of spiral.

The corrugations 2 and 3 upon the roll 1 may be arranged at any desired degree or pitch of spiral.

Specification of Letters Patent. Patented NOV. 30, 1920.

In some instances I prefer to space the corrugations 3 farther apart than the corrugations 2 on the roll 1, and I may form the corrugations 3 of any desired depth and width suflicient to allow coarse middlings to escape through them from between the rolls, thereby insuring the desired delivery of such coarse middlings in an unbroken condition.

The advantages of this construction are that in the grinding operation the largest and best middlings are permitted to escape from the rolls through the second series of corrugations 3 without being broken and in their original large and coarse condition.

I do not limit myself to any particular pitch, spacing or depth, for the corrugations upon the roll.

In Fig. 1 of the drawings I have shown the roll 1 provided with a suitable driving pulley 7, and the roll 4 provided with a larger pulley 8. With this arrangement of pulleys the rolll may be driven at a greater rate of speed than the roll 4, thereby securing a suitable differential between the speeds of the rolls. Any suitable preferred driving means for the rolls may be employed.

l/Vith this arrangement of the two sets of corrugations, 2 and 3, crossing each other at an angle on the roll 1, this roll is provided with a series of points or short ribs, the length thereof depending upon the width of spacing of the corrugations. The opposite roll being also provided with corrugations which may be parallel with its axis or arranged spirally thereon, and with means being provided for driving one roll at a greater speed than the other, the grain is disintegrated by means of a series of points, one series moving at a higher rate of speed, and passing the other series moving at a lower rate of speed. This mode of operation produces a shelling or picking action of the middlings out of the berry with little or no crushing action. I thereby get a very superior granulating action of the roll reducing the whole interior of the berry to the maximum quantity of large, uniform middlings.

I claim as my invention:

1. A grinding roll having a series of spiral corrugations and having also a second series of spiral corrugations crossing the first series of corrugations at an angle thereto, the corrugations of the roll forining between thern interrupted ribs having all sides 7 downwardly and outwardly sloping.

2. In an apparatus ifor producing flour from wheat or other graln, a grlnding roll having spiral corrugations, and having also a second series of spiral corrugations, -run- 7 ni-ng at an angle to the first series of corrugations, the corrugations of the roll forming between them interrupted ribs having all sides downwardly and outwardly sloping, in combination with a coiiperating' grindingroll 1n grinding relatlon thereto,

from Wheat or other grains, a grinding roll having a series of spiral corrugations, and having also a second series of spiral corrugations crossing the first series of corrugations at an angle, the corrugations of theio'll forming between them interrupted ribs having all sides downwardly and outwardly sloping, in-combination with a cooperating grinding rollhaving a series of spiral corrugations, and arranged in grinding relation thereto, and rneans for driving said rolls at different rates of speed,f:sub-

stantially as described.

:In witness whereof, I' have hereunto set my hand this 15th day of November, 1918.

4 EDWARD F. CLARK. 

